(1) Field of the Invention
The invention relates to a swirl jet nozzle which is designed for use as a hydraulic tool. More particularly, this invention is directed to enhancing the reliability and service life of tools which employ a pressurized liquid to remove material from a surface. Accordingly, the general objects of the present invention are to provide novel and improved apparatus and methods of such character.
2. DESCRIPTION OF THE PRIOR ART
Known tools which can be used in particular for the cleaning of pipes or tanks consist, for example, of an inner stator having a central bore which is connectable to a high-pressure source of water or other liquid. Such tools also include a rotor, coaxially arranged around the outside of the stator and having ports for the discharge of jets of liquid which perform the desired material cutting and/or removal function. The rotor is also driveable by the pressurized liquid.
Such known tools are complicated in structure since they require bearings and seals or bushes between the rotor and stator. Due to the complicated structure and the requirement that the rotatable connection between the rotor and stator be maintained by means of a screw connection on the stator or by means of a brake, the known tools have relatively large outer dimensions which prevents their use in, for example, the cleaning of com paratively small diameter pipes. Most importantly, previously available hydraulic tools did not establish a floating bearing of the rotor on the stator which was ope rationally reliable and thus there was a constant risk of seizure.